You need an ETA for Puerto Rico if you have a Hungarian passport

Travellers need a travel authorization to visit Puerto Rico for Business or Tourism. The Electronic System for Travel Authorization (ESTA) is an online application that determines the eligibility of visitors to enter Puerto Rico. Once the application is approved, travellers receive their ESTA confirmation electronically. A valid ESTA is required to visit the country. If the ESTA is expired or doesn’t match the traveller’s passport information, travellers will not be able to board their flight. An ESTA is electronically linked to a passport and valid for 2 years. If travellers receive a new passport, they must apply for a new ESTA. United States permanent residents or holders of valid United States visas don’t need an ESTA.